GE Masoneilan 4700E, Руководство по обслуживанию

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Masoneilan 4700P/E & 4800P/E Positioners Manual =
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51 © 2015 General Electric Company. All rights reserved
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Field Mounting and Complete Calibration, Rotary
Actuators
The following instructions are to be followed for mounting and calibration of the 4700P/4700E
and 4800P/4800E positioner. Define the proper valve action and positioner action. If the position-
er is not on the valve, see Figure 20 on page 71 to mount positioner and cam coupling. Once the
positioner body is assembled on the valve and the coupling is on the valve shaft, proceed to the
proper section below.
Air to Open / Direct Acting Positioner
See Figure 19 on page 68 and Figure 20 on page 71.
1. Do not connect air supply or signal to the positioner. Valve is closed.
2. Place lever S/A (3) to proper side (left or right) as designated by the appropriate
cam selection table for valve in question.
3. With valve closed, place cam holder (36) with Truarc ring (37) into cam coupling
(34).
4. Place the cam (26) onto the cam holder (36) so that the selected cam lobe is facing
forward and will rest on the cam follower. (See appropriate table for cam
selection.) Secure cam to cam holder with washer (27) and screw (28). Tighten the
screw (28) while holding the cam (26).
5. With the valve closed, place the desired cam lobe's low signal line on the cam
follower (4A). With the low signal line resting on the cam follower, sight across the
face of the cam to the raised reference line on the positioner case and align. (Low
signal line and reference line.) Center cam between the two arms of the lever S/A
(3), then tighten set screws (35) to 87 inch-lbs torque. (See Figure 19 on page 68 for
cam mounting.)
6. Connect air supply and signal to positioner. Connect positioner output to valve
actuator. Refer to connection diagram. Adjust signal to low end of signal (i.e., 3 psig
for a 3-15 psig range 4700P/4800P; 4 mA for 4-20 mA 4700E/4800E).
7. Adjust zero and span. Refer to “Zero Adjustment” on page 48 and “Span
Adjustment” on page 48.
Air to Open / Reverse Acting Positioner
See Figure 19 on page 68.
1. Do not connect air supply or signal to the positioner. Valve is closed.
2. Place lever S/A (3) to proper side (left or right) as designated by the appropriate
cam selection table for valve in question.
3. Run an independent regulated air line to the valve actuator in place of positioner
output line. Slowly apply proper air pressure through the regulator to open the
valve. (Handwheel may be used to open the valve in place of regulated air line.)
Align the travel indicator with the open end of travel scale. Do not over travel.